Threat sensors that stand up to hostile environments.

If your design challenge is to create the best motion sensor or motion detector - fire sensor or fire detector, smoke sensor or smoke detector - you've come to the right company.  Dexter's sensor technologies are at multiple fronts today, reducing the threat of combat on land, sea and air.  Yet the industry leading advantages of Dexter sensors - low cost, high sensitivity, low energy consumption and long life - make them the perfect motion sensor for home, office and facility applications.

Dexter thin-film and silicon detectors can target precise threats, whether defined by movement, temperature or body mass.  Intensive MIL-STD-883H testing performed by Trialon Corporation, an independent testing facility, confirm that Dexter Research's silicon-based temperature sensor detectors meet the same rugged requirements of 1,000G's for mechanical shock and 30G's in random vibration for which our thin-film detectors are famous.  Download Dexter's report here (PDF).

And here's another fact:  Dexter's customers report that our detectors are still working in the field as long as thirty years after deployment.  Proof that we take mission critical assignments as seriously as you do.  For more information, contact


Click on any column heading in the table below to re-sort the listing of products in this application category by the specific characteristic of the Dexter detectors.

Thermopile Model# of ChannelsThermopile TechnologyPackage SizeActive Area Size (mm)Output Voltage (μV)Signal to Noise RatioResistance (kΩ)Time Constant (ms)
M5 1 Thin Film TO-5 0.5 Dia 35 5,000 3 28
ST60 TO-5 1 Silicon TO-5 .61 x .61 110 3,513 60 18
1M 1 Thin Film TO-5 1.0 Dia 60 8,571 3 32
ST120 1 Silicon TO-5 1.2 x 1.2 190 4,953 90 25
ST150 1 Silicon TO-5 1.5 x 1.5 295 8,159 80 37
2M 1 Thin Film TO-5 2 x 2 250 19,531 10 85
ST60 Dual 2 Silicon TO-5 .61 x .61 62 1,981 60 18
DR26 2 Thin Film TO-5 2 x .6 54 5,684 5.5 38
ST120 Dual 2 Silicon TO-5 1.2 x 1.2 165 4,301 90 25
ST150 Dual 2 Silicon TO-5 1.5 x 1.5 230 5,990 90 38
SLA32 2 x 16 Silicon 0.97" x 1.27" DIP .05 x .65 14.8 423 76 7

World’s Best Low-Cost Motion Sensor

Motion. We depend on it for all of our work processes and home security. But we also measure motion and regulate it. We want to know when someone is present and automatically light the way in the dark or open a door for convenience. We may want to turn on video surveillance. We also want to know if an intruder has violated secure space and trigger an alarm or possibly detain him in the space he just invaded.

What is a sensor and how does a motion sensor provide this automated surveillance security to detect the presence of a body and to trigger a programmed response?

What kind of security system surveillance sensor is the best? After all, there is a choice between active sensors—ultrasonic, microwave, or tomographic—or passive systems or PIR that use infrared detector sensors.

Because of their simplicity and reliability, passive infrared sensors are the #1 choice of among all competing space and motion detector technologies. Because the PIR has become so popular, Dexter Research supports OEM’s to make the technology as reliable as possible.

At the core of Dexter Research Center’s Thermacon is the best passive infrared detector sensor in the world, the thermopile, manufactured by Dexter Research Center. Dexter’s infrared detector components are rugged, which is why they were chosen for numerous space shuttle flights and will soon go to the Moon, and why Dexter components are the backbone of US military combat ground vehicles and aircraft fire suppression. They can be precisely targeted to as little as a tenth of one degree Celsius. Dexter’s infrared detectors are an excellent choice for designs to prevent false alarms when used for in-home security, workplace security and request to exit applications.

Dexter’s PIR based Thermacon products can be deployed to detect the presence of natural body heat. Because they are passive motion detectors, they emit no signals to help an intruder identify their placement for the purpose of evading or neutralizing them. And Dexter Thermacon motion sensors are reliable and far more durable and energy efficient green than competing technologies.

The Advantages of Passive Infrared (PIR) Explained

Objects above absolute zero and all living creatures emit energy in the form of infrared radiation. Electronic devices designed for such a purpose can detect this infrared radiation, which is otherwise invisible to the human eye. These devices are call “passive” because PIR devices do not generate or radiate any energy for detection purposes. They work entirely by detecting the energy given off by other objects and require no external power source to function as detectors.

Dexter Research’s PIR Thermacons detect changes in temperature at their targeted focal point. When a human, friend or intruder or an object, enters the zone being observed, a Dexter Thermacon PIR detects a change from room temperature to body or object temperature. This triggers the detection. Objects that have the same temperature as the monitored room will not trigger detection.

This motion sensor technology may be deployed to detect a homeowner, office or plant worker, customer, or an intruder. When a human enters the Field of View of the PIR motion detector, a change of energy occurs from room temp to the human’s temperature. This results in the generation of a detection signal. If the system is armed, depending on the system’s assigned tasks, a light will come on, a door will open or close, a door will lock or unlock, video turns on, or an alarm will result.

Multi-Sensing Capabilities

In addition to sensing motion, Dexter Research’s world-renowned passive infrared detectors are excellent for monitoring temperature, fire, gas, a loss of heating or cooling, or temperature differentials between sensitive interacting media.

One or more of these additional detecting capabilities can be packaged with a motion sensor. Again, because of their simplicity and reliability for performing these additional monitoring duties, Dexter’s Thermacon cores are an excellent choice for any multi-sensing unit.

With nearly four decades of successful collaborations on commercial and military design applications, Dexter is currently seeking manufacturing and distribution relationships with these new, state-of-the-art integrated multi-sense devices. Beyond our collaboration and engineering skills, Dexter Research also brings small batch and volume manufacturing capabilities to any relationship.

A superior Dexter Thermacon PIR motion sensor will detect an intruder, light a room, reduce heating and cooling costs, trigger video surveillance, or grant a request to exit, depending on its assigned task. Email to ask any question, develop specifications for a proposal, or to get your project started now.

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